After working together for more than a year, DocuSign has agreed to purchase its partner, Cartavi, in a deal of undisclosed size. Through the deal, electronic signature provider DocuSign said that it will help real estate professionals manage the end-to-end real estate transaction.

Cartavi is kind of like Dropbox for online real estate documents, helping real estate professionals store, manage and share those documents with clients or other real estate professionals. As part of today’s deal, DocuSign also announced a deeper integration with ZipLogix.

Together, DocuSign CEO Keith Krach said that they will be able to advance their leadership in real estate “by further streamlining transactions to make it easier, faster, and more convenient than ever to complete deals.”

DocuSign was founded in Seattle, but its headquarters is now in San Francisco. The company will retain its operations in Seattle and San Francisco, and Cartavi and its approximately 10 employees will stay in Chicago. The business, which was started in 2009 and raised its first round of financing last year, will continue to operate under the name Cartavi.

The deal makes sense, in part because DocuSign is already the e-signature provider for the National Association of Realtors. More than one million members of the NAR already have access to DocuSign, with the company on the whole boasting some 37 million users.

However, a number of Multiple Listing Services across the country, including the Northwest Multiple Listing Service in the Seattle area and the Silicon Valley Association of Realtors, have chosen DocuSign rival Authentisign. Real estate agents in Western Washington now get discounted access to Authentisign as part of their subscription to the NWMLS, making DocuSign a more expensive option.

The purchase of Cartavi could help woo some of those real estate customers back, providing additional tools to manage documents.